Vehicle steering truck and method of making same



May l, 1945. c. E. FRUDDEN VEHICLE STEERING-TRUCK AND METHOD OF MAKINGSAME Filed July 18, 1941 2 Sheets-Sheet l May 1, 1945. c. E. FRUDDENVEHICLE STEERING TRUCK AND METHOD OF MAKING SAME 2 sheets-sheet 2 FiledJuly 18, 1941 Illlll im] mum I. /z 2324 ff sul Patented May 1, 1945UNITED sfrn'ras PATENT oFFIcE VEHICLE STEERING TRUGK AND METHODl F GSAM-E ConradE. Frudden, Wauwatosa, Wis., assignor to. Allis-ChalmersManufacturing ompanxn` Milwaukee, Wi's., a corporation of DelawareApplication 4Jul-y 18, 1941,.S'erialfN.o-. 402291K:

` 6' Claims.

The.. invention .relates to.. improvements iin thet construction and..manutacture of .steering trucks. for. vehiclesr particularly'. of. thetypein. which a pair ofsupporting Wheels. are rotatably. mounted on arigid. axle,4 andin whiclrsteering: isaefected by pivotal adjustment ofthe axle about aniupright axisbetween said'wheels.

The mentioned..steering..r principle. is. common in tractors which have.a pair of.. steerable.;iront Whee1s,.and particularly where suchl frontrwheels: are arranged in. close'proximity toteachlother', as in farmtractors.

lItis anobject. of theinventiortto.l provid-eau, improved Vehiclesteering truck in which apair. of wheels. are. rotatably mounted. on a,steerable. axle, and in which an uprightsteering.: spindle. issecured.toy a portionv of said axle betweenlthe wheels.

More specifically, `itv isan obj/ect of :thesinvention to provide animproved construction and method, ofV manufacture .of the. turnable'support short; distance.- aheadrofl the. wheel centers,. so. that; when.the tractory is;.in motion, the steer'-v abl'e wlie'els. are .subjectto; swivel.. movement. like the wheel. of acaster.

IThe improved construction of.. thev axle and spindle: assembly',..andtheimprovedmethod. of'

l effect which tends to hold the. wheels` on a onv which .the wheels'.are; mounted, vthat is,; ofthe.

axle; and. spindle assemblyv which is steerably mounted. on astationarypart of thewsteering. truck..

Another and-important object of :the invention is to obtain. a savingoflcosts'. in. the production of the turnable wheel support, ascomparedheretofore employedconstructions and methods of manufacture, and. toeffect such saving. of costs; without sacrificing strength and otherrequire-- ments,v or features whichare desi1able=..from. a performance:standpoint in operation of' the. vehicle.

In steering trucks for farm tractors?whichv have. a pair of closelyspacedfront wheelszsuch wheels.

are preferably-mounted torrotate;indownwardlyconverging planes, the.purpose being. to provide' a relatively narrow spacing oft the wheelsbelow the axle: and a relativelygwid'e; spacing' of. the. wheels. abovethe. axle. The relatively narrow' spacing' of the. wheels. below theaxle. enablesv them to run. in a narrow space loetween'twov pliant rows,while the relatively wide spacing ofl the wheels above the axle providesroomk for the. steering spindleand. for a downward extension of thestationary part of the steering truckA onwhich'; tnesteering spindle' ismounted.

For convenience oflthe. operatorin' driving the tractor itis furtherdesirable that when he swings the steer-able wheels .to the right-o1"left'for-Ysteering, the Wheels should' have a tendencyA to returnvautomatically to a straight ahead'` position', and for thatpurpose-'theaxis onwhich'the straight aheadcourse.

As ya iirst step-"towards providingl a relatively inexpensive a-Xle'and.spindle assembly incorporating theA mentioned 1. two features, theinvention contemplates to. mach-ine. astraight axle blank of standardbar stock in a lathe or screw ma.- chine toform wheel spindles atopposite ends of the blank, .the axes ofA the wheel spindles coincidingsubstantially with the longitudinal axisv of .the blank. The blank. islonger than the combined axial lengths of. the spindles, that is, it.hasan. intermediate. portion, of vordinarily appreciable length4 betweenthe spindles, and OI" reasons ofA economy the machining: in the lathe orscrew machine .is preferably limited to the end portions of the blankwhich` requiremachining to form the spindles thereon,` and'such limitedmachining therefore leaves any intermediate portion of.' the blankunmachined.'

After the wheel spindles are formedon the blank it is bent to providefor the required angul'arity between the axes of the wheel spindleswhich angularity causes the Wheels, when mounted on said spindles', toturnY in the inentioned relatively converging planes. Preferably, theblank is bentcold and about' a' single center, which can be done verycheaply. In order to facilitateH the bending, the axle blank may beweakened locally betweenthe.. wheel` spindles, as bycutting a'transverse grooveintoxit from one S side. Ifsuch a'grooveis cutintofthe` axle blank,

the bend is preferably` performed in the direction which causes awidening ofthe groove at the side ofY the blank from which the groove iscut into it.l

The steering spindle is formed as a separate piece-'from the axle, whichmakes" it possible to convenientlyl perform any machining operations onthe steering'spin'dla which may be necessary or'd'esirab1e,prior to'itsassembly withthe axle.

steering spindle."turnsl is preferably arranged a Likewise', the' Wheelspindles ofthe axle may conveniently be shaped in the mentioned mannerprior to the assembly of the axle with the steering spindle, and thebending of the axle blank is also preferably performed prior to saidassembly.

As stated, a transverse groove may be cut into the axle to facilitatethe bending thereof for angling the axes of the wheel spindles, and thesteering spindle may be connected with such a grooved axle, after it isbent, in a simple and inexpensive manner which affords not only adequatestrength of the axle and spindle assembly to withstand the substantialloads to which it is subjected in operation of the tractor, but whichmanne;` of connection also affords the mentioned caster eiect whichtends to hold the wheels on a straight ahead course. For that purposethe groove is made so that after bending of the axle it tapers inwardlyfrom the surface of the axle, the converging side Walls of the groovebeing preferably straight, and one end of the steering spindle istapered to conform` substantially with the taper of the groove. Thetapered end of the steering spindle is then set into the axle groove inan offset position relative to the axle, that is, in a position in whichthe axis of the steering spindle is spaced transversely from the axes ofthe angled wheel spindles. The` cross-section of the bar stock fromwhich the axle is made affords a sufficient thickness of the axle at thegroove so that, when the axis of the steering spindle is offset from theaxes of the wheel spindles a proper distance to afford the desiredcaster effect, at least part of the taperedend of the steering spindleis received within the groove.

After the steering `spindle has been arranged relative to the axle inthe mentioned offset position, with its axis spaced from the axes of theWheel spindles a proper distance to afford the desired caster effect andwith at least part of its tapered end received within the axlefgroove,the axle and spindle are then directly united by fusion of metal,preferably by welding. The described arrangement of the axle andsteering spindle affords suitable corners between relatively ad jacentsurface portions of the axle and spindle for depositing a fillet offusedi'vmetal therein, and a strong fused metal connection between' theaxle and steering spindle may therefore be made conveniently and atrelatively low costs.

The local weakening of the axle, as by cutting a groove into it, makesit possible to bend it with relatively little effort for angling thewheel spindles, but such angling may also be accomplished by bending theaxle without prior local weakening of an intermediate portion thereof.As pointed out hereinbefore, the machining ofthe axle blank in a latheor screw machine preferably leaves the intermediate portion of the axlebetween the wheel spindlesunmachined,l andthe axle, if bent withoutprior local weakening, will have an intermediate distorted portion ofthe full thickness, or of Substantially the full thickness, of the barstock from which the axle blank is made. In that case thev steeringspindle may again be connected to the bent axle, according to theinvention, in a simple and inexpensive manner which affords adequatestrength of the com'- pleted axle and spindle assembly and also providesfor the mentioned caster effect to hold the wheels on a straight aheadcourse. For instance, a transverse groove may be formed at one end ofthe steering spindle, which groove conformssubstantially with 'theprofile of the intermediate e to said axle portion by welding.

axle portion of full thickness, and the grooved portion of the steeringspindle may be connected By suitably matching the spindle and axleprovision may be made for spacing the axis of the steering spindle fromthe axes of the wheel spindles a proper amount to alford the mentionedcaster effect of the wheels. That is, when the axle abuts the matchedportion of the steering spindle, contact of the spindle and axle insuresthe desired proper spacing of the axis of the steering spindle from theaxes of the wheel spindles, and the desired location of the axlelongitudinally of the steering spindle. After the spindle and axle havebeen arranged in the mentioned abutting relation to each other, they aredirectly united by a fused metal connection between the matched portionsthereof. The abutting arrangement of the n grooved steering spindlerelative to the full thickness of the axle, like the abuttingarrangement of the tapered steering spindle relative to the grooved axlewhich has been referred to hereinbefore, affords suitable cornersbetween relatively adjacent surface portions of the axle and spindle fordepositing a llet of fused metal therein, as by welding.

Generally stated, the invention contemplates a castering support for apair of wheels, comprising an axle and a steering spindle; in which theaxle has opposite wheel spindles; in which the steering spindle isrotatable about an axis olset from the axes of the wheel spindles; inwhich the axle and steering spindle have matched integral portions inthe space between the axis of the steering spindle and a plane extendingparallel to the axis of the steering spindle through the axes of thewheel spindles; and in which a fused metal connection unites the axleand steering spindle at said matched portions thereof.

The foregoing and other objects and advantages of the invention willbecome more `fully apparent from the following description of severalembodiments of the invention illustrated in the accompanying drawings.Referring to the drawings, in which like reference characters designatethe same or similar parts in the several views:

Fig. 1 is a sectional front view of a steering truck for a farm tractor;

Figs. 2 to 9 illustrate various stages of manu'- faeture of the axle andspindle assembly of the steering truck shown in Fig. 1

Figs. 10 to 14 illustrate various stages of manufacture of Aa modifiedaxle and spindle assembly.

Referring to Fig. l, the stationary part of-the steering truck comprisesa housing section l and a spindle guide 2 which extends downwardly fromthe housing section l and is secured thereto by a series of bolts 3.Bolts 4 in lateral wing portions of the housing section I serve to holdthe stationary lpart of the steering truck in xed position on thetract-or, and a radiator S which forms part of the tractor is mounted onthe upper housing section l by means of a bracket structure l.

The stationary part of the steering truck is supported on a pair ofrubber tired supporting wheels 8 and 9 by means 'of an axle and spindleassembly which comprises a cambered axle H and a steering spindle l2,and which assembly is constructed and manufactured as follows.

- Referring to Fig. 2, this ligure shows the axle l I in an initialstage of its manufacture. The dashdotted lines in Fig. 2 indicate theoutline of a blank which is obtained by cutting a piece of suitablelength from a round bar of cold` rolled steel, such bar being straightas vit comes from themill',` and. its diameter.k being` indicated. at..I EL in Fig. 2. The ends of the. straightaxlefblank are turned downinalathe or screw machine to. form axially alined spindle portions for thewheels 8 and. 9 thereon, the alinedaxes ofthe spindle portions.coinciding substantially withthelongitudinal axis of the blank. andeachspindle portion comprising. aseat I4 for the inner race ofv a.roller bearing I6 shownin Fig. l and aseat Il for the. inner race ofanother roller bearing I-.8.which is likewise shown. in Fig. 1. Theseats IA` andi] are connected. by a tapered portion t therebetween, andeach. spindle terminates ina threaded portion I9 for the reception-oraretaining, nut 2I shown in Fig. 1.. The machining. of lthe blank in thelathe or screw machine ispreferably limited'ito the end portions whichrequire'machiningto.form the spindles and screw threads, while anintermediate portion 22 of the blank remains unmachined.

After the forming of the spindle. portions on the blank, a transversegroove 23 is cutinto the intermediate portion 22 of the blank at oneside thereof, the groove extending in the direction. of its lengthtransversely of the axle II, as shownv in' Figs. 3 and 6. The groove 23has relatively inclined straight side walls and a depthapproximatelyequal to the radius of the bar stock from which the blank is made.

After the formation of the spindleportions and. the groove, the axle isbent at the portion. thereof which has been weakened by the groove23,..as shown in Fig. 4, to dispose the axes of the spindle portionsangularly relative to each other. The weakening of the intermediate.portion 22' of the axle, by cutting the groove 23 into it, makes itpossible to bend the axle, while cold,l into the shape shown in Fig. 4with relatively little eiort, and the direction of said bending is suchas to increase the width of the groove at the periphery of the axleportion 22. In other words, the axle bar is bent at its intermediateportion so as to enlarge the -groove in the direction of its width.

The steering spindle I2 has a conical end portion 24 as shown in Figs. 5.and 6 of a taper corresponding substantially to the' taper at which theside walls of the groove 23 are disposed relative to each other by thementioned bending of the axle. The conical end of the steering spindle'I2 is set into the groove 23 of the axle in an offset position relativeto the latter, as shown in Fig. 8, in which olfset position thel axis ofthe steering spindle is spaced a short distance from the axes of thespindle portions of the bent axle II, and

, about one-half of the conical end 24 of the steering spindle, at oneside of its axis, is received within the groove 23 of the axle. Therelatively angled axes of the spindle portions of the axle extend in acommon plane, and in the mentioned offset position. of the steeringspindle its axis extends parallel to said plane in a direction bisectingthe angle between the axes of the wheel spindles.

A short sleeve 26 is slid over a portion of the steering spindleimmediately adjacent to the tapered end 2li thereof, prior to the iinalfastening of the steering spindle to the axle. Preparatory to such finalfastening the axle and steering spindle are arranged in the relativeposition in. which they are shown in Figs. '7, 8 and 9, that is, thesteering spindle is placed to extend longitudinally into the groove 23in the direction of the depth of the latter.

After the steering spindle I2, with the sleeve 26 placed thereon, hasbeen arranged relative 30 the groove.

portions of.- the. intermediate. axle portion 22:, then' atoppositesidesof. the. groove 23. and peripherally ofthe axle Il. along. thelower end.of the. sleeve 26 and the. adjacent upper surface portions of the. axleII, and. finally into the space of` the groove 23 which. isleft open bythe. offsetting of the. steering. spindle I2 relative to theaxler. II,as may best be seen from Figs. 8 and.9. Arear.- ward portion of the:ksteering spindle which is united with the axle. by the portion ofthe:fillet weld Within the groove, anda forward. portion. of. thesteeringspindle which is. united .with the. axle by the portionsr of.the llet weld along the mentioned front corners,..are spacedfroineachother in the longitudinal direction. of the groove 23. The illetweld, therefore, directly units the. axle and steering spindle. withinthe groove. and: at portions of the steering spindle which. are spacedfrom each other in the longitudinal .direction of. The end of the sleeveadjacentto theaxle II istapered to facilitate the deposit of weldedmaterial uniting the sleeve 2B with the axle Il and with the lower endyof the' steering spindle; I2.

In the steering truck as shown in Fig. l, the steering spindle I2 is`rotatably mounted in. the: spindle guideA 2 by means of a conicalro-llerbearing 29 in a lower. part of the spindle guide 21, and by meansof a running fit of the steering spindle in an axial bore 3| in anupperpart of thee spindle guide.. The mentioned sleeve 26 provides an. axialabutment for the inner race of the roller bearing. 29, which inner raceis press-fitted upon the steering spindle. A seal 32 is arranged belowvthe roller bearing 29y between the sleeve 26 and a skirt portion at thelower end of the spindlev guide 2. The spindle I2 is thus mounted on thestationary part of thev steering truck for rotation. about asubstantially vertical axis, and the unitedaxleand spindle are soarranged in the steering truck that, due to the offset relation betweenthe spindle I2 and the axle l I, the. axis of rotation of the spindle I2is spaced a short. distancek forwardly from the axes of the wheelspindles on the axle II. When the tractor is in motion, the wheels 8 and9 will therefore be subject to swivel movement like the wheel of a hubof' the bevel gear Stand is retained on the spindle I2 by means of abolt 36. In order t0 steer the wheels 8 and 9 to the right or left, ro-

tary movement is transmitted to the steering spindle I2 by .means of atransverse steering. crank 31 which hasa bevel gearv segment 38. in4mesh with` the. bevel gear 33. within the housing; section4 I, and anouter crank arm 39 for rocking the steering crank about its axis. Themechanism for transmitting steering movements to the steering spindle bymeans of the transversely disposed steering crank 3l is the subject of acopending application, Serial No. 402,296, filed on July le, 1941, byWalter F. Strehlow for Tracton and now Patent No. 2,301,152, datedNovember 3, 1942.

The steering spindle I2 is made from round bar stock of cold rolledsteel which, after being cut to a proper length, is suitably machined toform the conical portion 24 at one end of the steering spindle, theaxial splines. 2'I at the other end thereof, and a smooth, preferablyground surface at an intermediate portion of the spindle aiording arotary running fit of the spindle in the bore 3I of the spindle guide 2.Another smooth, preferably ground surface is formed near the lower endof the steering spindle for a press-fit with the sleeve 2B and with theinner race of the roher bearing 29. For convenience of manufacture thementioned smooth surfaces, the splines 2l, and the tapped hole for thereception of the bolt 35 are preferably formed on the spindle I2 beforeit is Welded to the axle I I.

Referring again to Figs, 7, B and 9, it will be noted that the describedwelded connection between the axle II and the steering spindle I2 issuch as to compensate substantially for the weakening of the axle whichis caused by the cutting of the groove 23 into the intermediate portionthereof. The tapered end of the steering spindle I2 coacts with theadjacent portions of the axle to take up compression forces to which theupper half of the axle is subjected due to the downwardly directed loadcomponents transmitted thereto through the steering spindle I2 and dueto the upwardly directed load components transmitted thereto through thewheels 8 and 9.

Shrinkage of the axle during the cooling period after the fillet weld 28has been applied causes the bent axle to straighten out to some extent,that is, the angle at which the axes of the wheel spindles are disposedrelative to each other slightly increases, at the lower side of theaxle, during the cooling period after welding. In order to obtain apredetermined angle between the axes of the wheel spindles in thecompleted axle and spindle assembly, it is therefore necessary to bendthe axle, prior to its connection with the steering spindle, somewhatbeyond said predetermined angle. If the desired camber of the axle, thatis, the angle between the axes of the wheel spindles in the completedassembly is, for instance, 170 degrees, the axle is preferably bent,prior to its connection with the steering spindle, to an angle of about165 degrees.

A modified construction and method of manufacture of the axle andspindle assembly is illus trated in Figs. 10 to 14 of the drawings. Inmaking the modified axle and spindle assembly, an axle blank like thatindicated by the dash-dotted lines in Fig. 2, is used and machined atits opposite ends to form the wheel spindles thereon as describedhereinbefore in connection with Fig. 2. After the forming of the wheelspindles on the axle blank, the axle is then bent, without locallyweakening the intermediate portion 22 thereof, into the shape shown inFig. 10, and the the profile of the intermediate bent portion of theaxle by the provision of a transverse groove 4I thereon. The groove 4Iforms an arcuate recess in the lower end of the spindle, the radius ofwhich is substantially the same as the radius of the bar stock fromwhich the axle is made so thatI the steering spindle and axle may beplaced into abutting relation to each other as shown in Figs. 12 and 13.The depth 0f the groove 4I is such that when the steering spindle andaxle are arranged in the abutting position shown in Fig. 13, the axis ofthe steering spindle I2 is spaced from the axes of the Wheel spindles aproper distance toafford the mentioned caster effect of the- Wheels 8and 9 in operation of the tractor. A sleeve 26, like the one shown inFigs. and 8, is placed on the steering spindle, as explainedhereinbefole in connection with the axle and spindle assembly shown inFig. 1, and the modified assembly is completed by welding the partstogether in the relative position in which they are shown in Figs. 12,13 and 14. As shown in these figures, a continuous llet 42 of weldedmaterial extends all around the inter- 'section of the steering spindleI2 with the axle II, a lower part of the llet being deposited in thecorner between the lower end face of the steering spindle I2 and theadjacent circumferential surface of the axle, and anupper part of thefillet being deposited in the corner between the lower tapered edge ofthe sleeve 26 and the adjacent circumferential surface portions of theaxle. Continuing from the lower towards the upper part of the fillet 42extends longitudinally of the steering spindle I2 and peripherally ofthe axle II within the corners between relatively adjacent portions ofthe steering spindle and axle at the opposite ends of the groove l I.

It will be noted that in the modified construction shown in Figs. 10 to14, as well as in the construction. shown in Figs. i to 9, the fusedmetal connection unites relatively adjacent portions of the sleeve 26and axle II, and also relatively adjacent portions of the steeringspindle I2 and axle II below the sleeve 26. In both embodiments of theinvention an upper part of the fused metal connection unites relativelyadjacent portions of the steering spindle, axle and sleeve at the lowerend of the latter, and a lower part of the fused metal connection unitesrelatively adjacent portions of the steering spindle and axle below thesleeve 26.

The modified construction shown in Figs. 12 to 14 has an advantage overthe construction shown in Figs. 7 to 9 in that it saves part of the frelatively large amount of welded material which is deposited in thegroove 23 of the axle as shown in Figs. 8 and 9, and therefore may bemanufactured at a somewhat lower cost.

While in the foregoing two embodiments of the invention have beendescribed in detail with reference to the drawings, it should beunderstood that it is not intended to limit the invention to the exactdetails of construction and manufacture explained hereinbefore, forvarious modifications within the scope of the appended claims may occurto persons skilled in the art.

It is claimed and desired to secure by Letters Patent:

1. In a vehicle steering truck, a pair of supporting wheels, and acastering support for said wheels comprising an axle member havingopposite spindle portions within said wheels, a spindle member betweensaid wheels rotatable about an axis offset transversely of the axes ofportion matching said groove, and a fused metal connection between saidintegral portions of said members retaining one within said groove ofthe other.

2. In a vehicle steering truck, a pair of supporting wheels, and acastering support for said wheels comprising a cambered axle havingopposite spindle portions within said wheels, a spindle member rotatableon an axis extending, in transversely oiset relation to the axes of saidspindle portions, within a plane bisecting the angle between'the axes ofsaid spindle portions, one of said members having a groove in anintegral portion thereof, and the other of said members having anintegral portion matching said groove, and a fused metal connectionbetween said integral portions of said members retaining one within saidgroove of the other.

3. In a vehicle steering truck, a pair of supporting wheels, an axlemember having opposite spindle lportions within said wheels, a spindlemember between said wheels rotatable about an axis offset from andextending transversely of the axes of said spindle portions, said axleand spindle members having matched integral portions in the spacebetween said axis of said spindle member and a plane extending parallelto the axis of said spindle member through the axes of said spindleportions, and a llet of fused metal directly uniting said axle andspindle members at said matched integral portions thereof.

4. In a vehicle steering truck, a pair of supporting wheels, an axlehaving opposite spindle portionswithin said wheels and a groove at itsupper side extending, at an intermediate portion of said axle, from onesidel of a vertical plane through the axes of said spindle portions tothe other side of said plane, a steering spindle hav ing an end portionwithin said groove at said one side of said plane, and a lillet of fusedmetal directly uniting said axle and steering spindle at said groove.

5. An axle and spindle assembly comprising a vertical steering spindle,an annular member surrounding a portion of said steering spindle abovethe lower end thereof, an axle oliset from the axis of said steeringspindle and extending transversely thereof below said annular memberyand a fused metal connection between relatively adjacent portions ofsaid annular member and said axle, and between relatively adjacentportions of said steering spindle and axle below said annular member.

6. An axle and spindlel assembly comprising a vertical steering spindle,an annular member surrounding a portion of said steering spindle spacedfrom the lower end thereof, an axle oi set from the axis of saidsteering spindle and extending transversely thereof below said annularmember, and a fused metal connection between relatively adjacentportions of said steering spindle, axle and annular member at the lowerend of the latter and between relatively adjacent portions of saidsteering spindle and axle below said annular member.

CONRAD E. FRUDDEN.

